:root {
                    --theme-primary: #6B7280;
                    --theme-secondary: #9CA3AF;
                    --theme-accent: #D1D5DB;
                    --theme-background: #F8F9FA;
                    --theme-surface: #FFFFFF;
                    --theme-text: #2C3E50;
                    --theme-muted: #6C757D;
                    --theme-border: #E9ECEF;
                    --theme-hover: rgba(102, 126, 234, 0.1);
                }